It's plain text in the generally accepted definition [1] of the term. It's not a binary file that requires special software to author. It's possible to read and

It's plain text in the generally accepted definition [1] of the term. It's not a binary file that requires special software to author. It's possible to read and write the files in a text editor. "Plain text" does not imply "natural language description", though I can see the term could be confusing. [1] https://en.m.wikipedia.org/wiki/Plain_text https://en.m.wikipedia.org/wiki/Plain_text